Abstract：The mechanical properties, microcosmic grains, plastic thinning rate and forming test FLD of SAPH440 automobile structural steel pickling plate were studied by tensile testing machine, forming testing machine, optical microscope (OM) and backscattered electron diffraction (EBSD). The plastic deformation ability of pickling plate under two improved steelmaking processes was analyzed. The results showed that the overall plastic deformation ability of the pickling plate treated with calcium and magnesium was slightly better than that of the pickling plate treated with magnesium. At the same time, the thickness reduction rate was measured, and the numerical variation law was consistent with that of work hardening index n value, plastic strain ratio r value and forming limit strain. The plastic thinning ability of hot-rolled plates for automobile structures could be quickly evaluated through static tensile tests under the condition of limited sample area.
2024, Vol. 42 
